The present invention relates to a spring retaining ring of the bowed, internal type.
Machines, tools and numerous other types of structures and equipment often include movable components which are to be secured in place. To achieve this goal, use is sometimes made of spring retaining rings which are mounted on one component to form an artificial shoulder lying in the path of the other component, i.e., the retained part. Retaining rings are of various types, including a so-called "bowed" ring which is of non-planar (non-flat) profile (e.g., see U.S. Pat. No. 2,487,802). A bowed ring is yieldable resiliently in an axial direction and thus is highly suited to take-up end play caused by component wear, or tolerances in groove location, or tolerances in dimensions of the components. Bowed rings also dampen vibrations and oscillations of the retained parts. While achieving those advantages, bowed rings maintain a tight grip radially against the bottom of the groove.
Bowed retaining rings can be of the "internal" or "external" type. As can be seen from FIG. 1, an internal bowed ring 10 is specifically configured and dimensioned so that its radially outer portion 12 fits into a circular internal groove 14 of one component 16 and its radially inner portion 18 lies in the path of the retained part 20 to be capable of making contact with the latter. Thus, an internal bowed ring is intended to engage the retained part with its convex side.
An external ring is specifically configured and dimensioned so that its radially inner portion fits into a circular external groove of one component and its radially outer portion lies in the path of the retained part. Thus, an external bowed ring engages the retained part with its concave side.
To insure proper functioning of a bowed retaining ring, it is important that the ring be correctly installed. In the case of a bowed internal ring, this has heretofore required that the ring be installed such that the bowed portion of the ring projects toward the retained part, i.e., that the convex side of the ring engage the retained part as noted above. However, it may occur that a bowed internal ring is installed backwards, e.g., during insertion by careless or untrained personnel. In such an event, the concave side 22 of the ring will face the retained part 20, as depicted in FIG. 2. This results in the behavior characteristics of the ring being altered, because the length of the effective moment arm of the force applied against the ring is changed. In that regard, attention is directed to FIG. 1 which depicts a side view of the moment arm M which extends from the outer edge of the ring to the place of contact of the ring with the retained part (the outer edge defining the fulcrum about which the bowed portion flexes). In FIG. 2, however, the bowed portion defines the fulcrum and the retained part engages the ring at a location spaced inwardly of the outer edge of the ring. Hence, the resulting moment arm M' omits that portion of the ring disposed within the groove 14, and the consequent performance of the ring may be substandard. In situations where the risk of such a substandard performance cannot be tolerated, bowed-type retaining rings have, for the above reasons, not been employed. As a result, advantage cannot be taken of the earlier noted advantages emanating from the use of bowed retaining rings, e.g., end play take-up vibration reduction, etc.
It is, therefore, an object of the present invention to minimize or obviate problems of the above-described type.
Another object is to provide a bowed internal spring retaining ring which functions acceptably regardless of its installed orientation.